(KTLA) – The Ventura County Sheriff’s Office has made an arrest in the death of a Jewish man who died after an alleged altercation with a pro-Palestinian demonstrator in California.

Loay Abdelfattah Alnaji, 50, of Moorpark, was arrested Thursday morning on a charge of involuntary manslaughter, the VCSO said in a news release. He is being held in lieu of $1 million bail.

Authorities say Paul Kessler, 69, died from a severe head injury after an altercation with Alnaji during dueling protests on Nov 5 in Thousand Oaks, California.

After the incident, the Jewish Federation of Los Angeles said Kessler was “struck in the head by a megaphone wielded by a pro-Palestinian protestor.”

Video showed him lying on the ground suffering from a head wound. He was transported to a hospital where he died the next day.

A few days after the incident, Ventura County Sheriff Jim Fryhoff said investigators had “not ruled out the possibility of a hate crime,” but they lacked enough evidence to determine if a crime had been committed.

It’s unclear what new evidence, if any, has been found to warrant the arrest. An announcement from the Ventura County District Attorney’s office is expected later Thursday.

Alnaji is a computer science professor at Moorpark College, a community college in Moorpark, California, according to the Los Angeles Times. However, his bio was no longer publicly available on the college’s website as of Thursday morning.

The JFLA released a statement in support of the arrest after it was announced.

“We are grateful for the swift work of the Ventura County Sheriff’s Department in response to the tragic death of Mr. Paul Kessler,” the statement said. “This arrest shows that violence towards our Jewish community will not be tolerated. We will continue to monitor the case to help ensure justice is served. Our heartfelt condolences continue to be with the family of Paul Kessler and may his memory forever be a blessing.”

Kessler was among a group of pro-Israel demonstrators who showed up at an event that was advertised as a peaceful gathering to support Palestinians. About 75 people in total were there and patrols in the area reported seeing no indication of violence 15 minutes before the altercation, officials said.

Investigators continue to ask that anyone with video of the incident reach out to them at this website.

Demonstrations have been widespread and tensions are escalating in the United States as the death toll rises in the Israel-Hamas war.

The Associated Press contributed to this report.